4
2 Present State of Mn-Zn and Ni-Zn Commercial
Technology
2.1 Historical Rechargeable Manganese-Zinc Batteries
Single-discharge Mn-Zn cells are one of the most commercially successful battery
technologies in history, as they comprise the popular products from Energizer,
Duracell, Eveready, and other battery market competitors. They were first created
by Karl Kordesch, Lewis Urry and coworkers as reported, for example, in US Patent
2,960,558 in 1960. The Mn-Zn chemistry holds ~200 Wh per kg in an off-the-shelf
single-use Mn-Zn cell, at a retail cost of $40 per kWh. This outstanding performance motivated attempts to develop rechargeable Mn-Zn as early as the 1970s.
Briefly, the chemistry is believed to operate by a reaction pathway similar to
MnO H O e
MnOOH OH
at
Vvs Zn
2
2
1 1
l
~ .
.
(1)
2
2
2
4
2
2
2
MnOOH H O OH
Mn OH
MnO H O voltage independent
l
(2)
MnOOH H O e
Mn OH
OH
at
V vs Zn
l
2
2
0 9
~ .
.
(3)
2
2
2
4
2
2 4
2
MnOOH Zn OH
ZnMn O
OH
H O voltage independent
l
(4)
2
2
2
4
2
3 4
2
MnOOH Mn OH
Mn O
OH
H O voltage independent
l
(5)
where (1) and (3) are the energy storage reactions. Only specific crystal isomorphs
will yield these reactions, with reaction (1) being best done with “electrolytic
MnO 2 ” (EMD) and reactions (4) and (5) creating inactive byproducts hausmannite
(Mn 3 O 4 ) or haeterolite (ZnMn 2 O 4 ) which are irreversible. Further details are available in references [17–19]. More successful cycle life historically relied on additives such as titanium, bismuth, lead, or barium to reduce the dissolution reaction of
MnOOH to form Mn OH
4
2 thus preventing the formation of inactive hausmannite
[20–22]. Such chemistry formed the commercialization attempts of Rayovac
RENEWAL cells in the early 1990s, but unfortunately the capacity of this and similar additives did not typically survive over ~20 cycles, and customers did not accept
them. Recent work has continued with similar additives as discussed in Sect. 3.1,
e.g., see Table 1. Related developments at Ford Motor Co. in the late 1980s discovered bismuth additives to enable deep- cycling (close to 2 e
−
per MnO 2 , 600 mA g
−1
)
and long cycle life of MnO 2 under linear-voltage-sweep cycling conditions [26], but
unfortunately not during galvanostatic or constant power cycling, thus preventing
commercialization. A later company (RBC) continued research on this technology
but has not overcome this problem.
D. E. Turney et al.
2 Present State of Mn-Zn and Ni-Zn Commercial
Technology
2.1 Historical Rechargeable Manganese-Zinc Batteries
Single-discharge Mn-Zn cells are one of the most commercially successful battery
technologies in history, as they comprise the popular products from Energizer,
Duracell, Eveready, and other battery market competitors. They were first created
by Karl Kordesch, Lewis Urry and coworkers as reported, for example, in US Patent
2,960,558 in 1960. The Mn-Zn chemistry holds ~200 Wh per kg in an off-the-shelf
single-use Mn-Zn cell, at a retail cost of $40 per kWh. This outstanding performance motivated attempts to develop rechargeable Mn-Zn as early as the 1970s.
Briefly, the chemistry is believed to operate by a reaction pathway similar to
MnO H O e
MnOOH OH
at
Vvs Zn
2
2
1 1
l
~ .
.
(1)
2
2
2
4
2
2
2
MnOOH H O OH
Mn OH
MnO H O voltage independent
l
(2)
MnOOH H O e
Mn OH
OH
at
V vs Zn
l
2
2
0 9
~ .
.
(3)
2
2
2
4
2
2 4
2
MnOOH Zn OH
ZnMn O
OH
H O voltage independent
l
(4)
2
2
2
4
2
3 4
2
MnOOH Mn OH
Mn O
OH
H O voltage independent
l
(5)
where (1) and (3) are the energy storage reactions. Only specific crystal isomorphs
will yield these reactions, with reaction (1) being best done with “electrolytic
MnO 2 ” (EMD) and reactions (4) and (5) creating inactive byproducts hausmannite
(Mn 3 O 4 ) or haeterolite (ZnMn 2 O 4 ) which are irreversible. Further details are available in references [17–19]. More successful cycle life historically relied on additives such as titanium, bismuth, lead, or barium to reduce the dissolution reaction of
MnOOH to form Mn OH
4
2 thus preventing the formation of inactive hausmannite
[20–22]. Such chemistry formed the commercialization attempts of Rayovac
RENEWAL cells in the early 1990s, but unfortunately the capacity of this and similar additives did not typically survive over ~20 cycles, and customers did not accept
them. Recent work has continued with similar additives as discussed in Sect. 3.1,
e.g., see Table 1. Related developments at Ford Motor Co. in the late 1980s discovered bismuth additives to enable deep- cycling (close to 2 e
−
per MnO 2 , 600 mA g
−1
)
and long cycle life of MnO 2 under linear-voltage-sweep cycling conditions [26], but
unfortunately not during galvanostatic or constant power cycling, thus preventing
commercialization. A later company (RBC) continued research on this technology
but has not overcome this problem.
D. E. Turney et al.